Re: [HACKERS] psql's help (the LIMIT stuff)

Started by Bruce Momjianabout 27 years ago5 messages

maillist@candle.pha.pa.us

about 27 years ago

I hope the QUERY_LIMIT too.

I still have that cnfify() possible fix to review for KQSO. Are you
still thinking limit for 6.4 final, or a minor release after that?

I posted the part that is the minimum applied to 6.4 to make
adding LIMIT later non-initdb earlier. Anyway, here it's
again.

Already applied. I assume it is the same as the one I applied.

My LIMIT implementation that does it like the SET in the
toplevel executor (but via parsetree values) is ready for
production. I only held it back because it's feature, not
bugfix.

Do you want it in 6.4 final?

We are close to final, and can easily put it in 6.4.1, which I am sure
we will need, and if we split CVS trees, you'll have lots of minor
versions to pick from. :-)

Seems like it would be a nice minor release item, but the problem is
that minor releases aren't tested as much as major ones. How confident
are you in the code? What do others thing?

-- 
  Bruce Momjian                        |  http://www.op.net/~candle
  maillist@candle.pha.pa.us            |  (610) 853-3000
  +  If your life is a hard drive,     |  830 Blythe Avenue
  +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026

Import Notes

Reply to msg id not found: m0zWLoE-000EBPC@orion.SAPserv.Hamburg.dsh.de

Noname

jwieck@debis.com

about 27 years ago

In reply to: Bruce Momjian (#1)

I hope the QUERY_LIMIT too.

I still have that cnfify() possible fix to review for KQSO. Are you
still thinking limit for 6.4 final, or a minor release after that?

I posted the part that is the minimum applied to 6.4 to make
adding LIMIT later non-initdb earlier. Anyway, here it's
again.

Already applied. I assume it is the same as the one I applied.

Seen, thanks. Your 'Applied' just arrived after I packed it
again. It's the same.

We are close to final, and can easily put it in 6.4.1, which I am sure
we will need, and if we split CVS trees, you'll have lots of minor
versions to pick from. :-)

Seems like it would be a nice minor release item, but the problem is
that minor releases aren't tested as much as major ones. How confident
are you in the code? What do others thing?

I regression tested it, and did additional tests in the
SPI/PL area. It works. It only touches the parser and the
executor. Rules, planner/optimizer just bypass the values in
the parsetree. The parser and the executor are parts of
Postgres I feel very familiar with (not so in the optimizer).
I trust in the code and would use it in a production
environment.

It's below.

Jan

#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me. #
#======================================== jwieck@debis.com (Jan Wieck) #

diff -cr src.orig/backend/commands/command.c src/backend/commands/command.c
*** src.orig/backend/commands/command.c	Fri Oct 16 11:53:38 1998
--- src/backend/commands/command.c	Fri Oct 16 12:56:44 1998
***************
*** 39,44 ****
--- 39,45 ----
  #include "utils/mcxt.h"
  #include "utils/portal.h"
  #include "utils/syscache.h"
+ #include "string.h"

  /* ----------------
   *		PortalExecutorHeapMemory stuff
***************
*** 101,106 ****
--- 102,108 ----
  	int			feature;
  	QueryDesc  *queryDesc;
  	MemoryContext context;
+ 	Const		limcount;

  	/* ----------------
  	 *	sanity checks
***************
*** 113,118 ****
--- 115,134 ----
  	}

  	/* ----------------
+ 	 *	Create a const node from the given count value
+ 	 * ----------------
+ 	 */
+ 	memset(&limcount, 0, sizeof(limcount));
+ 	limcount.type		= T_Const;
+ 	limcount.consttype	= INT4OID;
+ 	limcount.constlen	= sizeof(int4);
+ 	limcount.constvalue	= (Datum)count;
+ 	limcount.constisnull	= FALSE;
+ 	limcount.constbyval	= TRUE;
+ 	limcount.constisset	= FALSE;
+ 	limcount.constiscast	= FALSE;
+ 
+ 	/* ----------------
  	 *	get the portal from the portal name
  	 * ----------------
  	 */
***************
*** 176,182 ****
  	PortalExecutorHeapMemory = (MemoryContext)
  		PortalGetHeapMemory(portal);

! ExecutorRun(queryDesc, PortalGetState(portal), feature, count);

  	if (dest == None)			/* MOVE */
  		pfree(queryDesc);
--- 192,198 ----
  	PortalExecutorHeapMemory = (MemoryContext)
  		PortalGetHeapMemory(portal);

! ExecutorRun(queryDesc, PortalGetState(portal), feature, (Node *)NULL, (Node *)&limcount);

  	if (dest == None)			/* MOVE */
  		pfree(queryDesc);
diff -cr src.orig/backend/executor/execMain.c src/backend/executor/execMain.c
*** src.orig/backend/executor/execMain.c	Fri Oct 16 11:53:38 1998
--- src/backend/executor/execMain.c	Fri Oct 16 20:05:19 1998
***************
*** 64,69 ****
--- 64,70 ----
  static void EndPlan(Plan *plan, EState *estate);
  static TupleTableSlot *ExecutePlan(EState *estate, Plan *plan,
  			Query *parseTree, CmdType operation,
+ 			int offsetTuples,
  			int numberTuples, ScanDirection direction,
  			void (*printfunc) ());
  static void ExecRetrieve(TupleTableSlot *slot, void (*printfunc) (),
***************
*** 163,169 ****
   * ----------------------------------------------------------------
   */
  TupleTableSlot *
! ExecutorRun(QueryDesc *queryDesc, EState *estate, int feature, int count)
  {
  	CmdType		operation;
  	Query	   *parseTree;
--- 164,170 ----
   * ----------------------------------------------------------------
   */
  TupleTableSlot *
! ExecutorRun(QueryDesc *queryDesc, EState *estate, int feature, Node *limoffset, Node *limcount)
  {
  	CmdType		operation;
  	Query	   *parseTree;
***************
*** 171,176 ****
--- 172,179 ----
  	TupleTableSlot *result;
  	CommandDest dest;
  	void		(*destination) ();
+ 	int		offset = 0;
+ 	int		count = 0;

  	/******************
  	 *	sanity checks
***************
*** 191,196 ****
--- 194,289 ----
  	estate->es_processed = 0;
  	estate->es_lastoid = InvalidOid;

+ 	/******************
+ 	 *	if given get the offset of the LIMIT clause
+ 	 ******************
+ 	 */
+ 	if (limoffset != NULL)
+ 	{
+ 		Const		*coffset;
+ 		Param		*poffset;
+ 		ParamListInfo	paramLI;
+ 		int		i;
+ 
+ 		switch (nodeTag(limoffset))
+ 		{
+ 			case T_Const:
+ 				coffset = (Const *)limoffset;
+ 				offset = (int)(coffset->constvalue);
+ 				break;
+ 
+ 			case T_Param:
+ 				poffset = (Param *)limoffset;
+ 				paramLI = estate->es_param_list_info;
+ 
+ 				if (paramLI == NULL)
+ 					elog(ERROR, "parameter for limit offset not in executor state");
+ 				for (i = 0; paramLI[i].kind != PARAM_INVALID; i++)
+ 				{
+ 					if (paramLI[i].kind == PARAM_NUM && paramLI[i].id == poffset->paramid)
+ 						break;
+ 				}
+ 				if (paramLI[i].kind == PARAM_INVALID)
+ 					elog(ERROR, "parameter for limit offset not in executor state");
+ 				if (paramLI[i].isnull)
+ 					elog(ERROR, "limit offset cannot be NULL value");
+ 				offset = (int)(paramLI[i].value);
+ 
+ 				break;
+ 
+ 			default:
+ 				elog(ERROR, "unexpected node type %d as limit offset", nodeTag(limoffset));
+ 		}
+ 
+ 		if (offset < 0)
+ 			elog(ERROR, "limit offset cannot be negative");
+ 	}
+ 
+ 	/******************
+ 	 *	if given get the count of the LIMIT clause
+ 	 ******************
+ 	 */
+ 	if (limcount != NULL)
+ 	{
+ 		Const		*ccount;
+ 		Param		*pcount;
+ 		ParamListInfo	paramLI;
+ 		int		i;
+ 
+ 		switch (nodeTag(limcount))
+ 		{
+ 			case T_Const:
+ 				ccount = (Const *)limcount;
+ 				count = (int)(ccount->constvalue);
+ 				break;
+ 
+ 			case T_Param:
+ 				pcount = (Param *)limcount;
+ 				paramLI = estate->es_param_list_info;
+ 
+ 				if (paramLI == NULL)
+ 					elog(ERROR, "parameter for limit count not in executor state");
+ 				for (i = 0; paramLI[i].kind != PARAM_INVALID; i++)
+ 				{
+ 					if (paramLI[i].kind == PARAM_NUM && paramLI[i].id == pcount->paramid)
+ 						break;
+ 				}
+ 				if (paramLI[i].kind == PARAM_INVALID)
+ 					elog(ERROR, "parameter for limit count not in executor state");
+ 				if (paramLI[i].isnull)
+ 					elog(ERROR, "limit count cannot be NULL value");
+ 				count = (int)(paramLI[i].value);
+ 
+ 				break;
+ 
+ 			default:
+ 				elog(ERROR, "unexpected node type %d as limit count", nodeTag(limcount));
+ 		}
+ 
+ 		if (count < 0)
+ 			elog(ERROR, "limit count cannot be negative");
+ 	}
+ 
  	switch (feature)
  	{

***************
*** 199,205 ****
  								 plan,
  								 parseTree,
  								 operation,
! 								 ALL_TUPLES,
  								 ForwardScanDirection,
  								 destination);
  			break;
--- 292,299 ----
  								 plan,
  								 parseTree,
  								 operation,
! 								 offset,
! 								 count,
  								 ForwardScanDirection,
  								 destination);
  			break;
***************
*** 208,213 ****
--- 302,308 ----
  								 plan,
  								 parseTree,
  								 operation,
+ 								 offset,
  								 count,
  								 ForwardScanDirection,
  								 destination);
***************
*** 222,227 ****
--- 317,323 ----
  								 plan,
  								 parseTree,
  								 operation,
+ 								 offset,
  								 count,
  								 BackwardScanDirection,
  								 destination);
***************
*** 237,242 ****
--- 333,339 ----
  								 plan,
  								 parseTree,
  								 operation,
+ 								 0,
  								 ONE_TUPLE,
  								 ForwardScanDirection,
  								 destination);
***************
*** 691,696 ****
--- 788,794 ----
  			Plan *plan,
  			Query *parseTree,
  			CmdType operation,
+ 			int offsetTuples,
  			int numberTuples,
  			ScanDirection direction,
  			void (*printfunc) ())
***************
*** 742,747 ****
--- 840,859 ----
  		{
  			result = NULL;
  			break;
+ 		}
+ 
+ 		/******************
+ 		 *	For now we completely execute the plan and skip
+ 		 *	result tuples if requested by LIMIT offset.
+ 		 *	Finally we should try to do it in deeper levels
+ 		 *	if possible (during index scan)
+ 		 *	- Jan
+ 		 ******************
+ 		 */
+ 		if (offsetTuples > 0)
+ 		{
+ 			--offsetTuples;
+ 			continue;
  		}

  		/******************
diff -cr src.orig/backend/executor/functions.c src/backend/executor/functions.c
*** src.orig/backend/executor/functions.c	Fri Oct 16 11:53:38 1998
--- src/backend/executor/functions.c	Fri Oct 16 19:01:02 1998
***************
*** 130,135 ****
--- 130,138 ----
  									 None);
  		estate = CreateExecutorState();

+ 		if (queryTree->limitOffset != NULL || queryTree->limitCount != NULL)
+ 			elog(ERROR, "LIMIT clause from SQL functions not yet implemented");
+ 
  		if (nargs > 0)
  		{
  			int			i;
***************
*** 200,206 ****

feature = (LAST_POSTQUEL_COMMAND(es)) ? EXEC_RETONE : EXEC_RUN;

! return ExecutorRun(es->qd, es->estate, feature, 0);
}

  static void
--- 203,209 ----

feature = (LAST_POSTQUEL_COMMAND(es)) ? EXEC_RETONE : EXEC_RUN;

! return ExecutorRun(es->qd, es->estate, feature, (Node *)NULL, (Node *)NULL);
}

  static void
diff -cr src.orig/backend/executor/spi.c src/backend/executor/spi.c
*** src.orig/backend/executor/spi.c	Fri Oct 16 11:53:39 1998
--- src/backend/executor/spi.c	Fri Oct 16 19:25:33 1998
***************
*** 791,796 ****
--- 791,798 ----
  	bool		isRetrieveIntoRelation = false;
  	char	   *intoName = NULL;
  	int			res;
+ 	Const		tcount_const;
+ 	Node		*count = NULL;

  	switch (operation)
  	{
***************
*** 825,830 ****
--- 827,865 ----
  			return SPI_ERROR_OPUNKNOWN;
  	}

+ 	/* ----------------
+ 	 *	Get the query LIMIT tuple count
+ 	 * ----------------
+ 	 */
+ 	if (parseTree->limitCount != NULL)
+ 	{
+ 		/* ----------------
+ 		 *      A limit clause in the parsetree overrides the
+ 		 *	tcount parameter
+ 		 * ----------------
+ 		 */
+ 		count = parseTree->limitCount;
+ 	}
+ 	else
+ 	{
+ 		/* ----------------
+ 		 *      No LIMIT clause in parsetree. Use a local Const node
+ 		 *	to put tcount into it
+ 		 * ----------------
+ 		 */
+ 		memset(&tcount_const, 0, sizeof(tcount_const));
+ 		tcount_const.type           = T_Const;
+ 		tcount_const.consttype      = INT4OID;
+ 		tcount_const.constlen       = sizeof(int4);
+ 		tcount_const.constvalue     = (Datum)tcount;
+ 		tcount_const.constisnull    = FALSE;
+ 		tcount_const.constbyval     = TRUE;
+ 		tcount_const.constisset     = FALSE;
+ 		tcount_const.constiscast    = FALSE;
+ 
+ 		count = (Node *)&tcount_const;
+ 	}
+ 
  	if (state == NULL)			/* plan preparation */
  		return res;
  #ifdef SPI_EXECUTOR_STATS
***************
*** 845,851 ****
  		return SPI_OK_CURSOR;
  	}

! ExecutorRun(queryDesc, state, EXEC_FOR, tcount);

  	_SPI_current->processed = state->es_processed;
  	if (operation == CMD_SELECT && queryDesc->dest == SPI)
--- 880,886 ----
  		return SPI_OK_CURSOR;
  	}

! ExecutorRun(queryDesc, state, EXEC_FOR, parseTree->limitOffset, count);

  	_SPI_current->processed = state->es_processed;
  	if (operation == CMD_SELECT && queryDesc->dest == SPI)
diff -cr src.orig/backend/parser/analyze.c src/backend/parser/analyze.c
*** src.orig/backend/parser/analyze.c	Fri Oct 16 11:53:41 1998
--- src/backend/parser/analyze.c	Fri Oct 16 13:29:27 1998
***************
*** 180,186 ****
--- 180,190 ----

  		case T_SelectStmt:
  			if (!((SelectStmt *) parseTree)->portalname)
+ 			{
  				result = transformSelectStmt(pstate, (SelectStmt *) parseTree);
+ 				result->limitOffset = ((SelectStmt *)parseTree)->limitOffset;
+ 				result->limitCount = ((SelectStmt *)parseTree)->limitCount;
+ 			}
  			else
  				result = transformCursorStmt(pstate, (SelectStmt *) parseTree);
  			break;
diff -cr src.orig/backend/parser/gram.y src/backend/parser/gram.y
*** src.orig/backend/parser/gram.y	Fri Oct 16 11:53:42 1998
--- src/backend/parser/gram.y	Sun Oct 18 22:20:36 1998
***************
*** 45,50 ****
--- 45,51 ----
  #include "catalog/catname.h"
  #include "utils/elog.h"
  #include "access/xact.h"
+ #include "catalog/pg_type.h"

#ifdef MULTIBYTE
#include "mb/pg_wchar.h"
***************
*** 163,169 ****
sort_clause, sortby_list, index_params, index_list, name_list,
from_clause, from_list, opt_array_bounds, nest_array_bounds,
expr_list, attrs, res_target_list, res_target_list2,
! def_list, opt_indirection, group_clause, TriggerFuncArgs

  %type <node>	func_return
  %type <boolean>	set_opt
--- 164,171 ----
  		sort_clause, sortby_list, index_params, index_list, name_list,
  		from_clause, from_list, opt_array_bounds, nest_array_bounds,
  		expr_list, attrs, res_target_list, res_target_list2,
! 		def_list, opt_indirection, group_clause, TriggerFuncArgs,
! 		opt_select_limit

  %type <node>	func_return
  %type <boolean>	set_opt
***************
*** 192,197 ****
--- 194,201 ----

%type <ival> fetch_how_many

+ %type <node>	select_limit_value select_offset_value
+ 
  %type <list>	OptSeqList
  %type <defelt>	OptSeqElem

***************
*** 267,273 ****
  		FALSE_P, FETCH, FLOAT, FOR, FOREIGN, FROM, FULL,
  		GRANT, GROUP, HAVING, HOUR_P,
  		IN, INNER_P, INSENSITIVE, INSERT, INTERVAL, INTO, IS,
! 		JOIN, KEY, LANGUAGE, LEADING, LEFT, LIKE, LOCAL,
  		MATCH, MINUTE_P, MONTH_P, NAMES,
  		NATIONAL, NATURAL, NCHAR, NEXT, NO, NOT, NULL_P, NUMERIC,
  		OF, ON, ONLY, OPTION, OR, ORDER, OUTER_P,
--- 271,277 ----
  		FALSE_P, FETCH, FLOAT, FOR, FOREIGN, FROM, FULL,
  		GRANT, GROUP, HAVING, HOUR_P,
  		IN, INNER_P, INSENSITIVE, INSERT, INTERVAL, INTO, IS,
! 		JOIN, KEY, LANGUAGE, LEADING, LEFT, LIKE, LIMIT, LOCAL,
  		MATCH, MINUTE_P, MONTH_P, NAMES,
  		NATIONAL, NATURAL, NCHAR, NEXT, NO, NOT, NULL_P, NUMERIC,
  		OF, ON, ONLY, OPTION, OR, ORDER, OUTER_P,
***************
*** 299,305 ****
  		INCREMENT, INDEX, INHERITS, INSTEAD, ISNULL,
  		LANCOMPILER, LISTEN, LOAD, LOCATION, LOCK_P, MAXVALUE, MINVALUE, MOVE,
  		NEW, NOCREATEDB, NOCREATEUSER, NONE, NOTHING, NOTIFY, NOTNULL,
! 		OIDS, OPERATOR, PASSWORD, PROCEDURAL,
  		RECIPE, RENAME, RESET, RETURNS, ROW, RULE,
  		SEQUENCE, SERIAL, SETOF, SHOW, START, STATEMENT, STDIN, STDOUT, TRUSTED, 
  		UNLISTEN, UNTIL, VACUUM, VALID, VERBOSE, VERSION
--- 303,309 ----
  		INCREMENT, INDEX, INHERITS, INSTEAD, ISNULL,
  		LANCOMPILER, LISTEN, LOAD, LOCATION, LOCK_P, MAXVALUE, MINVALUE, MOVE,
  		NEW, NOCREATEDB, NOCREATEUSER, NONE, NOTHING, NOTIFY, NOTNULL,
! 		OFFSET, OIDS, OPERATOR, PASSWORD, PROCEDURAL,
  		RECIPE, RENAME, RESET, RETURNS, ROW, RULE,
  		SEQUENCE, SERIAL, SETOF, SHOW, START, STATEMENT, STDIN, STDOUT, TRUSTED, 
  		UNLISTEN, UNTIL, VACUUM, VALID, VERBOSE, VERSION
***************
*** 2591,2596 ****
--- 2595,2601 ----
  			 result from_clause where_clause
  			 group_clause having_clause
  			 union_clause sort_clause
+ 			 opt_select_limit
  				{
  					SelectStmt *n = makeNode(SelectStmt);
  					n->unique = $2;
***************
*** 2602,2607 ****
--- 2607,2622 ----
  					n->havingClause = $8;
  					n->unionClause = $9;
  					n->sortClause = $10;
+ 					if ($11 != NIL)
+ 					{
+ 						n->limitOffset = nth(0, $11);
+ 						n->limitCount = nth(1, $11);
+ 					}
+ 					else
+ 					{
+ 						n->limitOffset = NULL;
+ 						n->limitCount = NULL;
+ 					}
  					$$ = (Node *)n;
  				}
  		;
***************
*** 2699,2704 ****
--- 2714,2794 ----
  		| ASC									{ $$ = "<"; }
  		| DESC									{ $$ = ">"; }
  		| /*EMPTY*/								{ $$ = "<"; /*default*/ }
+ 		;
+ 
+ opt_select_limit:	LIMIT select_offset_value ',' select_limit_value
+ 	{ $$ = lappend(lappend(NIL, $2), $4); }
+ 		| LIMIT select_limit_value OFFSET select_offset_value
+ 	{ $$ = lappend(lappend(NIL, $4), $2); }
+ 		| LIMIT select_limit_value
+ 	{ $$ = lappend(lappend(NIL, NULL), $2); }
+ 		| OFFSET select_offset_value LIMIT select_limit_value
+ 	{ $$ = lappend(lappend(NIL, $2), $4); }
+ 		| OFFSET select_offset_value
+ 	{ $$ = lappend(lappend(NIL, $2), NULL); }
+ 		| /* EMPTY */
+ 	{ $$ = NIL; }
+ 		;
+ 
+ select_limit_value:	Iconst
+ 			{
+ 				Const	*n = makeNode(Const);
+ 
+ 				if ($1 < 1)
+ 					elog(ERROR, "selection limit must be ALL or a positive integer value > 0");
+ 
+ 				n->consttype	= INT4OID;
+ 				n->constlen	= sizeof(int4);
+ 				n->constvalue	= (Datum)$1;
+ 				n->constisnull	= FALSE;
+ 				n->constbyval	= TRUE;
+ 				n->constisset	= FALSE;
+ 				n->constiscast	= FALSE;
+ 				$$ = (Node *)n;
+ 			}
+ 		| ALL
+ 			{
+ 				Const	*n = makeNode(Const);
+ 				n->consttype	= INT4OID;
+ 				n->constlen	= sizeof(int4);
+ 				n->constvalue	= (Datum)0;
+ 				n->constisnull	= FALSE;
+ 				n->constbyval	= TRUE;
+ 				n->constisset	= FALSE;
+ 				n->constiscast	= FALSE;
+ 				$$ = (Node *)n;
+ 			}
+ 		| PARAM
+ 			{
+ 				Param	*n = makeNode(Param);
+ 				n->paramkind = PARAM_NUM;
+ 				n->paramid = $1;
+ 				n->paramtype = INT4OID;
+ 				$$ = (Node *)n;
+ 			}
+ 		;
+ 
+ select_offset_value:	Iconst
+ 			{
+ 				Const	*n = makeNode(Const);
+ 
+ 				n->consttype	= INT4OID;
+ 				n->constlen	= sizeof(int4);
+ 				n->constvalue	= (Datum)$1;
+ 				n->constisnull	= FALSE;
+ 				n->constbyval	= TRUE;
+ 				n->constisset	= FALSE;
+ 				n->constiscast	= FALSE;
+ 				$$ = (Node *)n;
+ 			}
+ 		| PARAM
+ 			{
+ 				Param	*n = makeNode(Param);
+ 				n->paramkind = PARAM_NUM;
+ 				n->paramid = $1;
+ 				n->paramtype = INT4OID;
+ 				$$ = (Node *)n;
+ 			}
  		;

  /*
diff -cr src.orig/backend/parser/keywords.c src/backend/parser/keywords.c
*** src.orig/backend/parser/keywords.c	Fri Oct 16 11:53:42 1998
--- src/backend/parser/keywords.c	Sun Oct 18 22:13:29 1998
***************
*** 128,133 ****
--- 128,134 ----
  	{"leading", LEADING},
  	{"left", LEFT},
  	{"like", LIKE},
+ 	{"limit", LIMIT},
  	{"listen", LISTEN},
  	{"load", LOAD},
  	{"local", LOCAL},
***************
*** 156,161 ****
--- 157,163 ----
  	{"null", NULL_P},
  	{"numeric", NUMERIC},
  	{"of", OF},
+ 	{"offset", OFFSET},
  	{"oids", OIDS},
  	{"old", CURRENT},
  	{"on", ON},
diff -cr src.orig/backend/rewrite/rewriteDefine.c src/backend/rewrite/rewriteDefine.c
*** src.orig/backend/rewrite/rewriteDefine.c	Fri Oct 16 11:53:46 1998
--- src/backend/rewrite/rewriteDefine.c	Fri Oct 16 13:48:55 1998
***************
*** 312,317 ****
--- 312,323 ----
  		heap_close(event_relation);

  		/*
+ 		 * LIMIT in view is not supported
+ 		 */
+ 		if (query->limitOffset != NULL || query->limitCount != NULL)
+ 			elog(ERROR, "LIMIT clause not supported in views");
+ 
+ 		/*
  		 * ... and finally the rule must be named _RETviewname.
  		 */
  		sprintf(expected_name, "_RET%s", event_obj->relname);
diff -cr src.orig/backend/tcop/pquery.c src/backend/tcop/pquery.c
*** src.orig/backend/tcop/pquery.c	Fri Oct 16 11:53:47 1998
--- src/backend/tcop/pquery.c	Fri Oct 16 14:02:36 1998
***************
*** 40,46 ****
  #include "commands/command.h"

static char *CreateOperationTag(int operationType);
! static void ProcessQueryDesc(QueryDesc *queryDesc);

  /* ----------------------------------------------------------------
--- 40,46 ----
  #include "commands/command.h"

static char *CreateOperationTag(int operationType);
! static void ProcessQueryDesc(QueryDesc *queryDesc, Node *limoffset, Node *limcount);

  /* ----------------------------------------------------------------
***************
*** 205,211 ****
   * ----------------------------------------------------------------
   */
  static void
! ProcessQueryDesc(QueryDesc *queryDesc)
  {
  	Query	   *parseTree;
  	Plan	   *plan;
--- 205,211 ----
   * ----------------------------------------------------------------
   */
  static void
! ProcessQueryDesc(QueryDesc *queryDesc, Node *limoffset, Node *limcount)
  {
  	Query	   *parseTree;
  	Plan	   *plan;
***************
*** 330,336 ****
  	 *	 actually run the plan..
  	 * ----------------
  	 */
! 	ExecutorRun(queryDesc, state, EXEC_RUN, 0);

  	/* save infos for EndCommand */
  	UpdateCommandInfo(operation, state->es_lastoid, state->es_processed);
--- 330,336 ----
  	 *	 actually run the plan..
  	 * ----------------
  	 */
! 	ExecutorRun(queryDesc, state, EXEC_RUN, limoffset, limcount);

  	/* save infos for EndCommand */
  	UpdateCommandInfo(operation, state->es_lastoid, state->es_processed);
***************
*** 373,377 ****
  		print_plan(plan, parsetree);
  	}
  	else
! 		ProcessQueryDesc(queryDesc);
  }
--- 373,377 ----
  		print_plan(plan, parsetree);
  	}
  	else
! 		ProcessQueryDesc(queryDesc, parsetree->limitOffset, parsetree->limitCount);
  }
diff -cr src.orig/include/executor/executor.h src/include/executor/executor.h
*** src.orig/include/executor/executor.h	Fri Oct 16 11:53:56 1998
--- src/include/executor/executor.h	Fri Oct 16 12:04:17 1998
***************
*** 83,89 ****
   * prototypes from functions in execMain.c
   */
  extern TupleDesc ExecutorStart(QueryDesc *queryDesc, EState *estate);
! extern TupleTableSlot *ExecutorRun(QueryDesc *queryDesc, EState *estate, int feature, int count);
  extern void ExecutorEnd(QueryDesc *queryDesc, EState *estate);
  extern HeapTuple ExecConstraints(char *caller, Relation rel, HeapTuple tuple);
  #ifdef QUERY_LIMIT
--- 83,89 ----
   * prototypes from functions in execMain.c
   */
  extern TupleDesc ExecutorStart(QueryDesc *queryDesc, EState *estate);
! extern TupleTableSlot *ExecutorRun(QueryDesc *queryDesc, EState *estate, int feature, Node *limoffset, Node *limcount);
  extern void ExecutorEnd(QueryDesc *queryDesc, EState *estate);
  extern HeapTuple ExecConstraints(char *caller, Relation rel, HeapTuple tuple);
  #ifdef QUERY_LIMIT

Oleg Bartunov

oleg@sai.msu.su

about 27 years ago

In reply to: Noname (#2)

I also would like to use Web-optimized postgresql in production.
Patched postgres (second trial) passed all regression test on my
Linux box and seems nothing was broken. How about
--enable-limit option to configure so people could make a choice ?

Regards,

Oleg

On Thu, 22 Oct 1998, Jan Wieck wrote:

We are close to final, and can easily put it in 6.4.1, which I am sure
we will need, and if we split CVS trees, you'll have lots of minor
versions to pick from. :-)

Seems like it would be a nice minor release item, but the problem is
that minor releases aren't tested as much as major ones. How confident
are you in the code? What do others thing?

I regression tested it, and did additional tests in the
SPI/PL area. It works. It only touches the parser and the
executor. Rules, planner/optimizer just bypass the values in
the parsetree. The parser and the executor are parts of
Postgres I feel very familiar with (not so in the optimizer).
I trust in the code and would use it in a production
environment.

It's below.

Jan

_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83

Bruce Momjian

maillist@candle.pha.pa.us

about 27 years ago

In reply to: Oleg Bartunov (#3)

I also would like to use Web-optimized postgresql in production.
Patched postgres (second trial) passed all regression test on my
Linux box and seems nothing was broken. How about
--enable-limit option to configure so people could make a choice ?

Regards,

It will be in 6.4, or in a minor release soon after 6.4.

-- 
  Bruce Momjian                        |  http://www.op.net/~candle
  maillist@candle.pha.pa.us            |  (610) 853-3000
  +  If your life is a hard drive,     |  830 Blythe Avenue
  +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026

Bruce Momjian

maillist@candle.pha.pa.us

about 27 years ago

In reply to: Noname (#2)

Seems like it would be a nice minor release item, but the problem is
that minor releases aren't tested as much as major ones. How confident
are you in the code? What do others thing?

I regression tested it, and did additional tests in the
SPI/PL area. It works. It only touches the parser and the
executor. Rules, planner/optimizer just bypass the values in
the parsetree. The parser and the executor are parts of
Postgres I feel very familiar with (not so in the optimizer).
I trust in the code and would use it in a production
environment.

It's below.

Haven't forgotten about this. Planned for the first minor release after
6.4. Hopefully I will have a cnf'ify/OR/palloc fix by then too.

-- 
  Bruce Momjian                        |  http://www.op.net/~candle
  maillist@candle.pha.pa.us            |  (610) 853-3000
  +  If your life is a hard drive,     |  830 Blythe Avenue
  +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026